Epidemiology of Chronic Critical Limb Ischemia

Peripheral artery disease (PAD) is often referred to as a continuum of disease of occlusive arterial syndromes that can range from asymptomatic obstructive disease through occlusive disease requiring amputation. This entire spectrum of PAD has prevalence as high as 20 % of the general population [ 1 ]. This spectrum becomes more progressive and symptomatic as the disease causes an imbalance of distal perfusion pressure to the tissue and metabolic demands within that tissue. On the latter end of this continuum, chronic critical limb ischemia (CLI) has a prevalence that is more diffi cult to defi ne and is quite variable in the published literature. Unlike asymptomatic PAD or exertional claudication, CLI occurs with inadequate perfusion at rest [ 2 ]. Like most of the terminology of peripheral vascular disease, the defi nitions of CLI have evolved over the years, with fi rst an increasing need to classify the entire continuum of PAD, the need to further classify those undergoing surgical procedures, and then to include more objective measures as well as the clinical presentation. In this chapter, we will discuss the epidemiology of CLI. We will present the historical background of CLI and the risk factors along with its clinical presentations and then after the epidemiology and prevalence of CLI along with its risk stratifi cation and prognostic data before discussing the socioeconomic impact of this disease. Defi nition of Chronic Critical Limb Ischemia